Special Senses Chapter 16 Flashcards
Where are:
-More than half of the sensory receptors in the human body located
Eyes
A large part of the cerebral cortex is devoted to processing _______ information.
Visual
(Accessory structures of the eye)
What is the:
-Eyelid
Palpebrae
(Accessory structures of the eye)
What is the:
-Layer of connective tissue which gives eyelid form and support
Tarsal plate
(Accessory structures of the eye)
What is:
-Located inside of the tarsal plates -secrete oils which keep eyelids from adhering to each other.
Tarsal glands (Meibomian glands)
What is:
-An infection of the tarsal gland producing a cyst on the eyelid
Chalazion
(Accessory structures of the eye)
What is:
-The thin protective membrane composed mainly of stratified columnar epithelium
Conjunctiva
(Accessory structures of the eye)
What:
-Lines inner eyelids
Palpebral conjunctiva
(Accessory structures of the eye)
What:
-Passes from the eyelids onto the anterior surface of the eye
(Does not cover the cornea)
Bulbar (Ocular) conjunctiva
What is:
-Inflammation caused by bacteria
-Other forms caused by irritants such as dust and smoke
Conjunctivitis (pink eye)
(Accessory structures of the eye)
What:
-Help protect from foreign objects, perspiration and sunlight
Eyelashes and Eyebrows
(Accessory structures of the eye)
What:
-Are found at base of eyelashes
Sebaceous glands
What:
-Is an and infection of sebaceous glands
Sty
(Accessory structures of the eye)
What is:
-The gap between the eyelids
Palpebral fissure
(Accessory structures of the eye)
What:
-Contains sebaceous and sudoriferous glands
Lacrimal caruncle
What:
-Manufactures and drains tears
Lacrimal Apparatus
(Lacrimal Apparatus)
Lacrimal gland drained by 6-12 ________ _______ ducts > Lacrimal puncta > superior and inferior ________ __________ > lacrimal sac > ____________ duct > inferior meatus (nasal cavity)
-Excretory lacrimal ducts
-Lacrimal canaliculi
-Nasolacrimal duct
What:
-Cleans, lubricates and moistens the eyeball
Lacrimal Secretion
What 4 things does the Lacrimal secrete?
How many ml/day is normal?
-Water
-Salt
-Mucus
-Lysozyme
-1ml/day
Describe the eye structure
-Hollow
-Spherical
-Approximately 1 inch in diameter
(Eye structure)
What contains:
-Sclera and cornea
Outer fibrous tunic
Which part of the eye:
-Focuses light onto retina
-Covers the iris
-Avascular
Cornea
(Eye structure)
What has these 3 layers:
-Nonkeratinized stratified squamous(outer)
-Collagen and fibroblasts (middle)
-Simple squamous (inner)
Outer fibrous tunic
Which part of the eye is:
-“white” of the eye
-Dense connective tissue
-Gives shape to the eye and makes it more rigid
Sclera
(Eye structure)
What contains:
-Choroid
-Ciliary body
-Iris
Vascular Tunic (Uvea)
(Eye structure)
What part of the eye:
-Highly vascular
-Provides nutrients to the posterior part of the retina
-Contains melanocytes to absorb light and prevent glare
Choroid
(Eye structure)
What contains:
-Ciliary processes
-Ciliary Muscle
Ciliary Body
(Ciliary Body)
What is:
-The extension of the ciliary process which hold the lens
Zonular fibers of lens
(Eye structure)
What is:
-The circular band of smooth muscle which alters the shape of the lens for far and near vision
Ciliary Muscle
What is the:
-A thin muscular diaphragm that regulates the amount of light entering eye
Iris
Which cells:
-Contain melanin
(amount of melanin determines eye color)
Chromatophores
The muscles:
Circular - Parasympathetic:
Does what to the pupil
Constricts pupil
The muscles:
Radial-Sympathetic:
Does what to the pupil
Dilate pupil
Which part of the eye:
-Contains a pigmented layer and neural layer
-Has 3 layers of _______ neurons
The Retina
Order of nerve conduction of the Retina:
Photoreceptor layer > Outer _________ layer > _________ neurons > Inner Synaptic layer > ___________ cells
-Synaptic layer
-Bipolar neurons
-Ganglion cells
What is the:
-Jagged anterior edge of retina
Ora serrata
What are the 2 types of photoreceptors called?
Rods and Cones
What is:
-Most important for black and white vision in dim light
-Allow us to see shapes and movement
Rods
In dim light such as moonlight, only ____ functions
Rods
What:
-Allows for color vison and sharpness of vison in bright light (visual acuity)
Cones
What are the 3 types of cones:
-Blue cones (S cones)
-Green cones (M cones)
-Red cones (L cones)
What is:
-The absence or deficiency of one of the 3 cones resulting in the inability to distinguish between certain colors
Color blindness
(Retina)
What is:
-A patch of cells in the exact center of posterior retina
-Contains a tiny pit called the fovea centralis
Macula lutea
(Retina)
What is:
-A dense concentration of cones in the macula (rods are absent)
-Area of our sharpest vision
Fovea centralis
What disorder is:
-Degeneration of the area of the macula lutea
-Usually 50 or over
-Loss of straight-ahead vision
-Retains peripheral vision
Age-related macular degeneration (AMD)
What disorder is:
-Distorted or lost vision in corresponding visual field
-Reattached by laser surgery or cryosurgery
Causes:
-Trauma, age-related degen. or various eye disorders
Detached retina
(Retina)
What is:
-Medial to the macula lutea
-______ ____is the opening through which axons of ganglion neurons exit as the optic nerve
Optic disc (blind spot)
(Retina)
What:
-Contains no rods or cones, so vision is absent here
Optic disc (blind spot)
What is:
-Behind the pupil and iris
-Made up of proteins called crystallins
-Is avascular and transparent
-Functions to focus images on the retina
Lens
What occurs when:
-Lens becomes cloudy due to changes in the lens proteins
-Most commonly occurs with aging
-Lens is replaced with an artificial one
Cataracts
What 2 cavities is the interior of the eyeball divided into
-Anterior cavity
-Vitreous chamber
The 2 chambers in the Interior of the eyeball is divided by what?
The lens
(Anterior cavity has 2 chambers)
Which chamber is:
-Between the cornea and iris
Anterior chamber
(Anterior cavity has 2 chambers)
Which chamber is:
-Behind the iris and in front of the lens
Posterior chamber
The anterior cavity is filled with a watery substance called the _________ _______.
-Aqueous humor
Aqueous humor is filtered from blood capillaries in the _______ _________.
It is drained by the _______ ______ ______ and then into blood.
-Ciliary process
-Scleral venous sinus
What nourishes the lens and cornea?
Aqueous humor
What disorder is:
-Abnormally high intraocular pressure due to build up of aqueous humor in the anterior cavity
-Persistent pressure leads to vision loss and blindness
Glaucoma
What disorder:
-The fluid can then put pressure on the lens and consequently the vitreous body and neurons of the retina
-Treated with eye drops to reduce production of aqueous humor and increase drainage
Glaucoma
What part of the eye:
-Lies between the lens and retina
The vitreous chamber
The jelly-like substance is called the…?
Vitreous body
The vitreous body is not replaced, but formed during __________ ______.
Embryonic life
Which part of the eye:
-Contains phagocytic cells which remove debris
The vitreous body
Which part of the interior eye:
-Narrow channel that runs through vitreous body
-In fetus, was occupied by the hyaloid artery
Hyaloid canal
(Image Formation)
Images are formed on the _______ of the eye.
Retina
(Image Formation)
-In order for an image to be formed, what 3 processes must be understood?
-Refraction
-Accommodation
-Constriction of the pupil
What occurs when:
-Bending of light rays as they travel from air into a different media
Refraction
What occurs at the:
-Cornea
-Aqueous humor
-Lens
-Vitreous body
Refraction of light
(Refraction)
-Images must focused directly on the _______ _________ where our sharpest vision is.
Fovea centralis
Images focused on the retina are ___________.
Inverted
What occurs when:
-Increased curvature of the lens for near vision
Accommodation
(Accommodation)
-When an object is closer than 20ft. light rays must be bent to a _________ ________ in order to focus images on the retina
Greater degree
(Accommodation)
-The ciliary muscle contracts pulling the ciliary process and _______ forward taking tension off the suspensory ___________.
(Allows the lens to become more rounded (thicker) for near vision)
-Choroid
-Ligaments
During accommodation, what also occurs
Constriction of the pupil
What prevents:
-Light rays from entering the periphery of the lens
Constricting the pupil
(Constriction of the pupil)
-Light rays entering the periphery of the lens would not ______ on the retina and thus cause _________ _______.
-Focus
-Blurred vision
What abnormality of refraction is:
-Nearsightedness
-Vision for near objects is better than for far
Myopia
What abnormality of refraction is:
-Error of refraction in which image is focused in front of the retina
-Eyeball too long from front to back, or the lens is thicker than normal
Myopia
What abnormality of refraction is corrected with:
-A concave lens causing the light rays to diverge slightly
Myopia
What abnormality of refraction is:
-Farsightedness
-Vision for far objects is better than for near.
Hyperopia (Hypermetropia)
What abnormality of refraction is:
-Error of refraction in which image is focused behind the retina
-Eyeball is too short from front to back, or the lens is thinner than normal
Hyperopia (Hypermetropia)
What abnormality of refraction is corrected with:
-A convex lens causing light rays to converge slightly
hypermetropia
What abnormality is:
-Irregularly shaped cornea or lens
Astigmatism
What abnormality is:
-Lens loses elasticity and therefore its ability to accommodate
-occurs with aging
-Results in hyperopia
Presbyopia
What is:
- A normal eye
Called?
Emmetrophic eye
What is it called when:
-Laser reshaping of the eye to correct refraction abnormalities
LASIK
(Sensory Transduction in the Retina)
-Images are focused on retina which stimulates _____________, which transduce(convert) the light stimulus into __________ ___________.
-Photoreceptors
-Receptor potentials
(Sensory Transduction in the Retina)
-Images are passed to ________ cells.
Bipolar
(Sensory Transduction in the Retina)
-Bipolar cells communicate with ___________ cells.
Ganglion
What are the 2 functions of the ear:
-Hearing
-Equilibrium
(External ear)
What is the:
-Elastic cartilage
called?
Auricle (Pinna)
(External ear)
What part of the ear is the:
-Lobule
-Helix
Auricle (Pinna)
The:
-Auricle (Pinna)
-External auditory canal
-Tympanic membrane (Eardrum)
Are in which part of the ear?
External (Outer) ear
What part of the ear is the:
-Air filled cavity in temporal bone
Middle ear
(Middle ear)
The:
-Malleus
-Incus
-Stapes
are all what?
Auditory ossicles
(External ear)
What are:
-Attached to the middle ear by ligaments, and also have 2 small skeletal muscles attached to them
Auditory ossicles
(Middle ear muscles)
Which muscle:
-Limits movement of and increases tension on the eardrum to prevent damage to the inner ear from loud sounds
Tensor tympani
(Middle ear muscles)
Which muscle:
-Is the smallest skeletal muscle
-Dampens large vibrations of the stapes due to loud noises
-Protects the oval window
Stapedius
(Middle ear)
What is located:
-From the middle ear to the pharynx
Auditory tube
(Pharyngotympanic or Eustachian tube)
(Middle ear)
What:
-Equalizes pressure between the middle ear and atmosphere
-Normally closed at its medial end and opens during swallowing and yawning
Auditory tube
(Middle ear)
What is the:
-Membrane covered opening between the middle and inner ear
-Stapes fits into it
Oval window
(Middle ear)
What is:
-Another opening just below oval window
-Covered by secondary tympanic membrane
Round window
What is:
-Acute infection of the middle ear usually caused by bacteria
-Pain, fever, malaise, reddening and outward bulging of the tympanic membrane
-Bacteria can pass through the Eustachian from the nasopharynx
Otitis media
What is:
-Inadequate drainage of fluid from the middle ear through the Eustachian tube may allow for bacteria to grow
-Children are more susceptible due to the auditory tubes being almost horizontal
Otitis media
What is the:
-Insertion of a small tube into the tympanic membrane to allow drainage
Tympanotomy
The Internal ear is also referred to as the:
Labyrinth
The 2 main divisions of the Labyrinth (Internal ear) are:
-Outer bony labyrinth
-Inner membranous labyrinth
What part of the ear has:
-A series of cavities in the petrous portion of the temporal bone
-Contains fluid called perilymph and surrounds membranous labyrinth
Bony labyrinth
The:
-Vestibule
-Cochlea
-Semicircular canals
Are the 3 parts of what?
The bony labyrinth
What part of the ear has:
-A series of sacs and tubes in bony labyrinth
-Contains fluid called endolymph
-Membranous labyrinth
What part of the ear is an:
-Oval central portion of the bony labyrinth
-Contains utricle and saccule which are part of the membranous labyrinth
Vestibule
What part of the ear has:
-3 bony canals at approximately right angles to each other
-Portion of the membranous labyrinth in semicircular canals
Semicircular canals
(Semicircular canals)
What is:
-The enlarged portions at end of canals
Ampulla
Which part of the ear is the:
-Bony spiral canal
Cochlea
Which part of the ear is divided into these 3 separate channels:
-Scala vestibuli
-Scala tympani
-Cochlear duct (Scala media)
Cochlea
(Cochlea)
-Scala vestibuli and tympani are joined at apex by the ___________.
Helicotrema
Which part of the Cochlea:
-Separates cochlear duct from scala vestibuli
Vestibular membrane
Which part of the Cochlea:
-Separates cochlear duct from scala tympani
Basilar membrane
The cochlea contains a bony central core called the _________.
Modiolus
Which part of the ear is:
-Located on the basilar membrane
-Consists of supporting cells and hair cells
Spiral organ (Organ of corti)
(Spiral organ (Organ of Corti))
What are:
-The receptors for auditory sensations
Hair cells
(Spiral organ (Organ of Corti))
What are:
-In contact with fibers
-cochlear branch of VIII cranial nerve
Basilar ends of hair cells
(Spiral organ (Organ of Corti))
What hair cells:
-Contain stereocilia
Apical end of the hair
(Spiral organ (Organ of Corti))
What is:
-In contact with hair cells
Tectorial membrane
(Physiology of hearing)
(1) Sound waves reach ear directed by the _____ into external auditory canal.
Pinna
(Physiology of hearing)
(2) Waves strike tympanic membrane causing it to ________.
Vibrate
(Physiology of hearing)
(3) Wave transmitted through ________, ______ and ________.
-Malleus, Incus and Stapes
(Physiology of hearing)
(4) Stapes pushes _____ _________ in and out
Oval Window
(Physiology of hearing)
(5) Movement of oval window causes waves in _________ of ________ __________.
-Perilymph
-Scala vestibuli
(Physiology of hearing)
(6) Pressure in perilymph pushes it through scala vestibuli, then _____________ into scala tympani and eventually to round window causing it to ______ __________.
-Helicotrema
-Bulge outward
(Physiology of hearing)
(7) As pressure moves through perilymph of the scala vestibuli, it pushes the vestibular membrane inward and increases the pressure of the ___________ inside the ___________ ________.
-Endolymph
-Cochlear duct
(Physiology of hearing)
(8) Vibration of basilar membrane causes movement of the _____ ______ of the spiral organ against the _________ ___________.
-Hair cells
-Tectorial membrane
(Physiology of hearing)
(9) Bending of the __________ develops receptor potentials that ultimately lead to generation of nerve impulses in the ________ branch of the vestibulocochlear nerve then eventually to the primary auditory area of the temporal lobe.
-Stereocilia
-Cochlear
(Physiology of hearing)
What type of waves:
-Vibrate basilar membrane near base of cochlea where membrane is stiffer
High frequency waves
(Physiology of hearing)
What type of waves:
-Vibrate basilar membrane nearer apex where membrane is more flexible
Low frequency waves
(Physiology of hearing)
-Each segment of the basilar membrane is _______ for a particular pitch
Tuned
What type of deafness is:
-Possible nerve damage (CN VIII)
-Usually damage to hair cells from certain medications, repeated exposure to loud sounds, atherosclerosis leading to decreased blood supply to ears
Nerve deafness (Sensorineural)
What type of deafness is:
-Problem is with the structure of the external and middle ear that conduct the sound to the cochlea
-Vibrations are not “conducted” to hair cells
Conduction deafness
What type of deafness results from:
-perforated ear drum
-Otosclerosis - overgrowth of spongy bone over the oval window that immobilizes the stapes
-Impacted cerumen
Conduction deafness
What would be used if:
-Deafness is due to destruction of hair cells
-Provides only a crude representation of sounds
Cochlear implants
What is:
-A microphone, sound processor and transmitter sends information to an internal receiver which relays to electrodes implanted in the cochlea
-Electrodes trigger nerve impulses in the cochlear branch of the vestibulocochlear nerve
Cochlear implants
(Physiology of Equilibrium)
-Body movements stimulate _________ for equilibrium
Receptors
(Physiology of Equilibrium)
The:
-Utricle
-Saccule in the vestibule
-Semicircular ducts of the semicircular canals
Are what? (2)
-Receptor organs
-Makeup the vestibular apparatus
What type of equilibrium is:
-Your perception of the orientation of your head in space
-Example: If your head is tilted in any direction
Static equilibrium
What type of equilibrium is:
-The perception of motor or acceleration
Dynamic equilibrium
(Equilibrium)
What type of acceleration is:
-A change in velocity in a straight line such as a car or elevator
Linear acceleration
(Equilibrium)
What type of acceleration is:
-A change in the rate of rotation such as turning your head or spinning in a chair
Angular acceleration
(Equilibrium)
What 2 things are responsible for:
-Static equilibrium and linear acceleration
The saccule and ultricle
(Equilibrium)
What:
-Detect angular acceleration
The semicircular ducts
The saccule and utricle both contain thickened regions called the ________
Macula
Where are these cell types found?
-Hair cells with stereocilia (microvilli_)
-1 cilium (kinocilium) - collectively called hair bundles
-Supporting cells that secrete gelatinous layer
In the Macula region
What contains:
-Calcium carbonate crystals called otoliths that move when you tip your head forward or backwards
Gelatinous otolithic membrane
(Otolithic Organs)
The ________ responds to horizontal linear acceleration and deceleration
(Speeding up or slowing down in a car)
Utricle
(Otolithic Organs)
-The ______ also responds to forward and backward head tilt
Utricle
(Otolithic Organs)
-The ______ responds to vertical linear acceleration and deceleration.
(Moving up & down in an elevator)
Saccule
(Otolithic Organs)
-With the utricle and saccule movements:
The hair bundles bend producing _________ __________ which release neurotransmitter which stimulates the ________ ________ of the vestibulocochlear nerve
-Receptor potentials
-Vestibular branch
(Semicircular ducts)
-3 semicircular ducts lie at right angles to each other in _____ ______ of ________.
-3 planes of motion
(Semicircular ducts)
What are:
-Small elevation within the ampulla of each of the 3 semicircular ducts
Crista
(Semicircular ducts)
-Hair cells with hair bundles are covered with gelatinous material called the ________
Cupula
(Semicircular ducts)
-With __________ acceleration and deceleration, fluid in canal bends ______ stimulating hair cells to release _______________ which generate action potentials in the vestibular branch of the __________________ nerve
-Rotational
-Cupula
-Neurotransmitter
-Vestibulocochlear
(Equilibrium pathways)
-Action potentials generated in the semicircular ducts, utricle, or saccule eventually reach: ?
Vestibular cortex of the parietal lobe
(Equilibrium pathways)
What:
-Controls movement of the head, eyes and postural muscles to maintain balance
Cerebellum
(Equilibrium pathways)
What is:
-Located in the spinal cord and descend to innervate extensor muscle to help you maintain balance with quick movements of the trunk and limbs
Vestibulospinal tracts
Which structure acts as a transducer in the spiral organ?
Inner hair cell
The spiral organ is housed within which structure?
Cochlear duct
Which structure allows upper respiratory infections to spread from the throat to the tympanic cavity?
Auditory tube
When you spin while sitting in a swivel chair with your eyes closed, you can sense this movement by means of your _________blank.
Semicircular ducts
Which of the following is not considered an accessory structure of the eye?
Cornea
